Method and apparatus for curving and heating aluminum sheets



Oct. 30, 1962 c. J. GAHLINGER 3,060,881

METHOD AND APPARATUS FOR CURVING AND HEATING ALUMINUM SHEETS Filed March 51, 1959 Sheets-Sheet l O IN 3% N Q ,g Q) ll.

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METHOD AND APPARATUS FOR CURVING AND HEATING ALUMINUM SHEETS Filed March 51, 1959 Y 2 Sheets-Sheet 2 8 Ol' q; 0

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CLARENCEJGAHJNGER ATTORNEYS Unite rates Patent Free 3,060,881 METHQD AND APPARATUS FOR CURVING AND HEATING ALUMINUM SHEETS Clarence J. Gahlinger, Valley Station, Ky., assignor to Reynolds Metals Company, Richmond, Va., 21 corporation of Delaware Filed Mar. 31, 1959, Ser. No. 803,179 23 Claims. (Cl. 113116) This invention relates to aluminum heating procedure.

When an aluminum sheet, or billet-like piece, or similar piece of aluminum is worked in aluminum working machinery to change its shape, ordinarily a flat sheet is formed which has been work hardened to a degree requiring it to be softened for further working or shaping. Ordinarily an annealing oven is provided through which such a sheet is passed to soften the sheet, after which it may be a further worked or shaped as desired. Such an annealing oven has conveying means extending through the oven from the feed end to the discharge end, but such conveying means tends to mar the flat sides of the sheet while it is being conveyed through the oven. The sheet then tends to retain such marred effect, and it is often d-ifiicult, and sometimes almost impossible to obliterate such marred effect in the finished product.

Some types of annealing or heating ovens have a plurality of parallel steel or similar metal conveying belts which become rough and rusted by their continuous passage through the annealing oven. When flat aluminum sheets are placed on these belts, rust and scratches tend to be placed on the fiat sides of the sheets which are diificult and sometimes substantially impossible of removal, without prohibitive expense.

According to this invention, the flat aluminum sheets which have passed through the aluminum sheet working machinery, and which have been work hardened to a degree requiring them to be softened for further working or shaping are passed through means to curve the sheet slightly with concave and convex sides substantially after they have been passed through the aluminum sheet working machinery and before being placed in the annealing oven. The sheets are curved sufiiciently to form concave and convex sides, so they may be placed with their concave sides downward on the conveying means in the annealing oven where they may be supported on their edges so they are not marred along their sides while passing through the oven. Accordingly it is an object of this invention to provide a method and apparatus for achieving this procedure.

Also, conveying means may be placed between the aluminum sheet working machinery and the annealing oven to convey the sheets from the machinery to the oven. Such conveying means may be provided with the means to curve the sheets with concave and convex sides as previously described, so that the sheets may be placed, by an operator, on the conveying mean of the oven with their concave sides downward to be supported on their edges and not to be marred along their sides. Accordingly it is an object of this invention to provide methods and means embodying the features set forth in this paragraph.

A belt conveyor may be used on which the fiat sheets may be placed after being worked in the sheet working machinery and before they are placed on the conveying means of the annealing oven. This belt conveyor may include means to curve the sheets, and to this end may include means to curve the belt conveyor transversely of its length to form an upwardly concave trough along its length. Pressing means may be placed in the concave trough to press the sheets downwardly to curve the sheets in the form of concave troughs. It is an object of this invention to provide means and methods for accomplishing the procedure as set forth in this paragraph.

The belt conveyor just described may be provided with curving means which includes a stationary, relatively rigid trough below the upper run of the belt conveyor and one or more wheels above said upper run and above said rigid trough to press the aluminum sheets downwardly into the trough and thus to curve the sheets with concave upward sides. The curved sheets may then be lifted from the conveyor and may be placed with such concave sides downward on the conveying means of the annealing oven so the sheets are supported on their edges, and do not have their sides marred by such conveying means while passing through the oven. It is also among the objects of this invention to provide means and methods for accomplishing these last described features.

Further objects and advantages will become apparent as the description proceeds with reference to the accompanying drawings, in which:

FIGURE 1 is a diagrammatic vertical illustration of an apparatus and method for practicing this invention.

FIGURE 2 is a top view of FIGURE 1.

FIGURE 3 is a top view of the stationary, relatively rigid trough which is placed underneath the upper run of the belt conveyor for curing the aluminum sheets.

FIGURE 4 is a cross-section taken along the line 44 of FIGURE 3.

FIGURE 5 is a cross-section along the line 55 of FIGURE 1.

FIGURE 6 is a cross-section along the line 66 of FIGURE 1.

FIGURE 7 is an enlarged and more detailed view of a portion of FIGURE 1.

FIGURE 8 is a top view of FIGURE 7.

FIGURE 9 is a cross-section along the line 9-9 of FIGURE 8.

According to this invention, aluminum sheets, billet-like pieces, or similar pieces of aluminum are worked in aluminum sheet working machinery or the like, such as rolling mills 20, through which a plurality of such sheets, etc.,

may be passed to emboss, elongate, or otherwise work and shape them. Such aluminum pieces may be passed automatically or manually from each of the machines 2% to the next, if desired. Eventually the aluminum pieces are made into flat sheets which are work hardened to a degree requiring them to be softened for further working. Sometimes such further working may require such sheets to be softened regardless of the degree of hardness produced by the machinery 20.

The word aluminum as herein used is intended to be considered in a broad sense to include substantially pure aluminum, aluminum alloys, and other metals and their alloys of a similar nature, as interpreted within the scope of this description.

The flat sheets produced by the machinery 20 are thereafter curved in the curving apparatus generally designated by the numeral 22 to produce sheets with concave and convex sides, such shape being of a temporary nature, if desired. For example, the sheet 24, FIGURE 1, may be a relatively long and narrow flat sheet which has been previously worked and produced in the working machinery 20. The sheet 24 passes through the curving machinery or means 22 and eventually takes the form of the upwardly concave sheet 26 at the left end of the couveyor or curving means 22. The curved sheet 26, and all similarly curved sheets of the series of sheets being processed, may be lifted by an operator working in the space adjacent the annealing or heating oven 28 who then places them with their concave sides downwardly, as indicated at 30. Such sheets are supported on their edges with their sides free from the conveying means 32 which convey the sheets through the annealing oven 28. The sheets 36 travel from the feed end 34 to the discharge end 36 of the oven. They may be lifted from the conveying means 32 at the discharge. end 36 and may be passed through one or more working or shaping operations diagrammatically illustrated by the machine 38, which requires sheets of the softness produced by the annealing oven 28. Such further working operation or operations may completely obliterate the temporary curved shape which was produced in the sheets prior to their placement on the conveying means 32 of the annealing oven.

More specifically, the working machinery my in clude one or a plurality of sets of rolls 40' which elongate the aluminum sheets, or similar aluminum pieces, into the form of the sheet 24. At this time the sheet 24 may be relatively long and narrow and flat, and has been work hardened to a degree requiring it to be softened for the further working which is to be performed in the apparatus 38. a

The combined curving and conveying apparatus 22 may include a sufliciently flexible belt made of canvas or the like which has an upper run 42 and a lower run 44, and which passes over the end rollers or pulleys 46 and 48. The roller 48 may be driven at the proper speed by the motor 50 through any suitable transmission, such as the drive belt 52, to drive the belt 42, 44 at proper speed. If desired, certain portions of the upper run 42 of the belt 42, 44 may be supported by the idler rollers 54 in a more or less fiat condition. 7

Means may be provided to curve the upper run 42 of the belt to form an upwardly concave trough along the length of the run 42. Also pressing means are placed in the concave trough to press the sheets downwardly and to curve the sheets along in the form of concave troughs such as sheet 26. To this end, a stationary, relatively rigid trough 56, FIGURES 3, 4 and 9-, is rigidly and stationarily supported underneath the upper run 42 of the belt in such a manner that the run 42 forms an upwardly concave trough, as indicated in FIGURE 9'. The means for pressing the sheet downwardly may include one or more wheels 58, 6t and 62 which are freely rotatable, and which are placed above the trough 56 in a manner gradually to curve the sheet from the flat shape of sheet 24, until it is fully curved as it passes under the last wheel 58. A sheet 64, FIGURES 7, 8 and 9, is shown receiving the final curving operation.

The trough 56, which is shown by itself in FIGURES 3 and 4, is'substantially flat at the end 70. Its sides 72 and 74 are gradually curved upwardly to form a gradually deeper trough. The maximum depth of the trough is obtained at the left end of the trough as indicated at 76. As the upper run 42 of the flexible belt 42, 44, passes over the trough 56, it assumes substantially the same trough-like contour of trough 56, since the run 42 is pressed downwardly by the wheels 58, 60 and 62 to maintain the run 42 substantially in contact with the top surface of the trough 56. The wheels 58, 60 and 62 may conveniently be automobile or truck wheels which have relatively large and flexible tires 78 pressing on the run 42. These tires 78 can yield while a sheet of aluminum, such as sheet 64, passes under the tires 78. The upper run 42 has a generally flat condition of the desired length at its right and left ends adjacent the rollers 46 and 48. The aluminum sheet 26 which has passed under wheels 58, 60 and 62 is in a transverse troughll'ke wn t Wi an Upper O ca c s d as h wn in FIGURE 6. The operator, who works in the space designated in general by the dotted line 88, FIGURE 2, lifts the curved sheets, such as sheet 26, from the conveyor 42, 44, and places the sheets with their concave sides downward as shown at 30 and preferably with the length of the sheet transverse to the direction of travel through the annealing oven 28.

The conveying means 32 in the annealing oven 28 generally consists of a plurality of parallel bands or belts 82,

made of steel, or similar metal, which belts 82 travel over the rollers 84 and '86 and are driven at the correct speed to maintain the sheets in the annealing oven the necessary length of timeto soften the sheet to the desired degree. The belts 82 continuously pass through the annealing oven where they are continuously subjected to bending action, such as when they pass over the rollers 84 and 86. The belts 82 are also subjected to continuous temperature changes as they pass through the heating and cooling sections of the oven. This causes the belts 82 to rust or corrode, and to become rough. Hence when flat aluminum sheets are laid on such belts 82, the sides of such flat sheets are quite likely to become marred by the rusted and rough condition of the belts 82, so that the surfaces of the aluminum sheets are discolored and scratched to such an extent that the subsequent operations performed at 38 do not remove the traces of such marring effect. The subsequent working or shaping operations which follow the annealing action are generally not intended to be polishing actions, so that the marred effect continues throughout subsequent operations, and cannot be removed without adding expensive polishing operations. Such polishing operations frequently do not remove the marred effect in a satisfactory manner.

Preferably the curving apparatus 22 is a unitary apparatus which is supported upon a framework such as diagrammtically illustrated in FIGURES 7 and 9. Such framework, for example, may include a plurality of vertical supports on each side of the belt 42, 44, which supports are connected to a base 92, with bracing 94, if desired. Also if desired, pedestals, slides, or other supports 90 may be provided and are of such a nature that the unit 22 may be moved along the factory floor. Preferably the unit 22 can be added to or removed from the conveying system which connects the working machinery 20 with the annealing oven 28. Some of the uprights 90 are secured to and support the trough 56 by means of the brackets 98, in an adjustable manner by bolts 99, if desired. Some of the uprights 90 also may be adjustably connected to hearings or supports 100, FIG- URE 9, which receive the shafts 102 which carry the wheels 5'8, 61') and 62. The adjustment of the bearings or supports 1% may be accompished by bolts 184 passing through suitable holes and slots in the uprights 90 and/ or the upright extensions 90a, as shown in FIGURE 9. If desired, the shafts 102 may turn in the bearings 1.08, or the shafts 1102 need not turn, and suitable bearings may be placed between the wheels and the shafts 182. in any case, the movement of theupper run 42 frictionally drives the wheels so they turn with the movement of the run 42. i i

The idler rollers 54 may be supported on fiat bars 183 which are secured to the proper uprights 90 on both sides of the belt 42, 44.

If desired, the temporary culving of the aluminum sheets produced by the working machinery may be incorporated or combined in the last machine 20 which operates on the aluminum pieces.

In operation, a plurality of aluminum sheets, billet-like pieces, or other aluminum pieces, are serially passed through one or more working machines 20*, where such sheets, or the like, are made longer, embossed, or other wise changed in shape normally to produce a plurality of flat sheets, may be relatively long and narrow, if desired, and which have been work hardened to a degree requiring them to. be softened for further working in steps such as produced by machinery diagrammatically indicated at 38. Such further working steps in machinery 38 may require the sheets to be as soft as they originally were before entering the machinery 20, or to be even softer than such original degree of hardness. The sheets that have been work hardened in machines 20 are con veyed to an annealing oven 28, which for example, has

a plurality of conveying belts 82 extending from the feed end 34 to the discharge end 36. Sometime before being placed on the conveying means 32 of the annealing oven 28, the sheets 24 which originally were flat, and long and narrow if desired, or which normally would be flat, are temporarily curved to provide a concave side and a convex side, such as shown at 26. Such curved sheets are placed on the oven conveying means 32 with their concave sides downward, as shown in FIGURE 1 at 30, so the sheets 30 are supported only on their edges and their sides are free from the conveying means 32. This prevents the sides from being marred while being conveyed through the oven 28. When the annealed sheets 3! emerge from the oven 28, they may be given a further working or shaping treatment in a machine such as 38 or any other treatment, as desired. This further treatment may obliterate the temporary curved condition previously produced by the curving means 22, or by curving means incorporated in the last working machine 20. Generally the edge portions of the sheets are trimmed off, so even the almost imperceptible marring at the edges is generally removed, or if left on, is practically imperceptible in the finished product.

While the form of the invention now preferred has been disclosed in accordance with the requirements of the statutes, other forms may be used, all coming within the scope of the claims which follow.

What I claim is:

1. In combination: support means; aluminum sheet working means operatively interconnected to said support means for serially changing the shape of a plurality of aluminum sheets and normally tending to produce a plurality of flat sheets which have been work hardened to a degree requiring them to be softened for further working; a heating oven means operatively interconnected to said support means and having a plurality of conveying belts adapted to convey said sheets through said oven means and tending to mar the fiat surfaces of said sheets when placed on said belts; and means operatively interconnected to said support means temporarily to curve said sheets to produce concave and convex sides so said sheets may be placed on said belts with their concave sides downward so they may be supported on their edges and are not marred along their sides.

2. A combination according to claim 1 in which working means is operatively interconnected to said support means to work said sheets after leaving said oven.

3. In combination: support means; aluminum sheet working means operatively interconnected to said support means for serially changing the shape of a plurality of aluminum sheets and normally tending to produce a plurality of flat sheets which have been work hardened to a degree requiring them to be softened for further working; an annealing oven means operatively interconnected to said support means and having conveying means extending through said oven means and tending to mar the fiat sides of said sheets while being conveyed through said oven; and means operatively interconnected to said support means temporarily to curve said sheets to produce concave and convex sides so said sheets may be placed on said conveying means with their concave sides downward so they may be supported on their edges with their sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven means.

4, A combination according to claim 3 in which working means is operatively interconnected to said support means to Work said sheets after leaving said oven.

5. A combination according to claim 3 in which said means to curve said sheets includes a belt conveyor carried by said support means and having an upper run, and in which combination a stationary relatively rigid trough carried by said support means and is placed below the upper run of said belt conveyor, and a wheel is carried by said support means and is placed above and in contact with said upper run and above said rigid trough.

6. In combination: support means; a belt conveyor carried by said support means and on which aluminum sheets may be placed after being worked by aluminum sheet working machinery and before they are placed in a heating oven; means carried by said support means to curve said belt conveyor transversely to form an upwardly directed concave trough along the length of said conveyor; and flexible and rotatable pressing means carried by said support means and extending into said concave trough to press said sheets downwardly into said trough to curve said sheets into the form of concave troughs.

7. A combination according to claim 6 in which a stationary relatively rigid trough is carried by said support means and is placed below the upper run of said belt conveyor, and a rotatable wheel is carried by said support means and is placed above and in contact with said upper run and above said rigid trough.

8. In combination with aluminum sheet working machinery for serially changing the shape of a plurality of aluminum sheets to produce a plurality of hat sheets which have been Work hardened and in combination with an annealing oven having a plurality of conveying belts extending from the feed end and extending from the discharge end of said oven and adapted to convey said sheets when placed on said belts: support means; means operatively interconnected to said support means to convey said sheets from said working machinery to said feed end of said oven; and means operatively interconnected to said support means and said convey ing means, to curve said sheets to produce concave and convex sides while being conveyed to said feed end so said sheets may be placed on said belts with their concave sides downward so they may be supported on their edges without being marred along their sides.

9. In combination with aluminum sheet working machinery for serially changing the shape of a plurality of aluminum sheets to produce a plurality of flat sheets which have been work hardened and in combination with an annealing oven having conveying means extending through said oven from the feed end to the discharge end of said oven and tending to mar the flat sides of said sheets while being conveyed through said oven; support means; means carried by said support means to curve Said sheets to produce concave and convex sides so said sheets may be placed on said conveying means with their concave sides downward so they may be supported on their edges with their sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven.

10. The method of fabricating aluminum products which comprises: working a sheet of aluminum to change its shape and normally to produce a relatively flat sheet which has been work hardened; curving said sheet to produce a concave side and a convex side; and placing said curved sheet with its concave side down on a conveyor which passes through a heating oven so said sheet is carried through said oven; and thereafter further work;- ing said heated sheet into a desired shape,

11. An apparatus for fabricating aluminum products Which comprises: support means; aluminum sheet Work ing means operatively interconnected to said support means for Working and changing the shape of said sheet to produce a relatively fiat sheet which has been work hardened; curving means operatively interconnected to said support means to curve said sheet to produce a concave side and a convex side in said sheet; an annealing oven means operatively interconnected to said support means to receive said curved sheet and having conveyor means passing through said oven means and upon which conveying means said curved sheet may be placed with its concave side down to rest on its edges on said conveying means so said sides are not marred; and means op eratively interconnected to said support means for further Working said sheet after it has been annealed in said oven.

12. The method of fabricating aluminum products which comprises: changing the shape of an aluminum sheet in aluminum working machinery to produce a flat sheet which has been work hardened; conveying said sheet to an annealing oven having a plurality of conveying belts adapted to convey said sheet through said even and tendingto mar the flat surfaces of said sheet when placed on said belts; curving said sheet to produce concave and convex sides while being conveyed to said oven; and placing said'sheet on said belts with its concave side downward so it may be supported on its edges without being marred along its sides.

13. The method of fabricating aluminum products which comprises: changing the shapeof an aluminum sheet in aluminum working machinery normally to produce a =flat sheet which has been work hardened; curving said sheet to provide concave and convex sides; and placing said sheet on the conveying means of an annealing oven having conveying means extending through said oven with the concave side of said sheet downward so'it may be supported on its edges with its sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven.

14. A method according to claim 13 in which said sheet is-further worked after leaving said oven.

15. The method of fabricating aluminum products which comprises: changing the shape of an aluminum sheet in aluminum working machinery to produce a relatively long and narrow flat sheet which has been work hardened; conveying said sheet to an annealing oven having a plurality of conveying belts adapted to convey said sheet through said oven and tending to mar'the flat surfaces of said sheet when placed on said belts; and curving said sheet transversely to its length to provide concave and convex sides while being conveyed to said oven; and placing said sheet on said belts with its concave side downward so it may be supported on its edges without being marred along its sides.

16. The method of fabricating aluminum products which comprises: changing the shape of an aluminum sheet in aluminum working machinery to produce a relatively long and narrow flat sheet which has been work hardened; curving said sheet transversely of its length to provide concave and convex sides; and placing said sheet on the conveying means of an annealing oven with the concave side of said sheet downward so it may be supported on its edges with its sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven.

17. The method of fabricating aluminum products which comprises changing the shape of a plurality of aluminum sheets in aluminum working machinery to produce a plurality of flat sheets which have been work hardened; conveying said sheets to an annealing oven and curving said sheets to provide concave and convex sides while being conveyed to said oven and placing said sheets on said belts with their concave sides downward 8 so they may be supported on'their edges without being marred along their sides.

7 18. The method of fabricating aluminum products which comprises: changing the shape of a plurality of aluminum sheets in aluminum working machinery to produce a plurality of flat sheets which have been work hardened; curving said sheets to provide concave and convex sides; and placing said sheets on the conveying means of an annealing oven with the concave side of said sheet downward so they may be supported on their edges with their sides free from said conveying means to prevent said sides from being marred While being conveyed through said oven.

19. A method according to claim 18 in which said sheets are further Worked after leaving said oven.

20. In combination, support means; an annealing oven means operatively interconnected to said support means and having conveying means tending to mar flat sides of aluminum sheets placed thereon, and an aluminum sheet disposed on said conveying means, said sheet being curved to produce concave and convex sides thereof and being disposed with its concave side downward to be supported on its edges with its sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven. r

21. The method of annealing an aluminum sheet which comprises: curving said sheet to provide concave and convex sides; and placing said sheet on the conveying means of an annealing oven with the concave side of said sheet downward so it may be supported on its edges with its sides free from said conveying means to prevent said sides from being marred while being conveyed through said oven.

22. In combination, support means, conveying means carried by said support means, means carried by said support means to curve said conveying means transversely along a length thereof to form a concave trough, and rotatable pressing means carried by said support means and extending into said concave trough to press flat sheets conveyed by said conveying means into said trough to curve said sheets into the form of concave troughs.

23. In combination, support means, conveying means carried by said support means, means carried by said support means to curve said conveying means transversely along a length thereof to form a concave trough, an aluminum sheet disposed on said conveying means, and rotatable pressing means carried by said Support means and extending into said trough pressing said sheet into said trough to curve said sheet into the form of a concave trough.

References Cited in the file of this patent UNITED STATES PATENTS 644,025 White Feb. 20, 1900 717,069 Bray Dec. 30, 1902 2,202,018 McCutcheon May 28, 1940 2,423,554 Davidson July 8, 1947 2,482,734 McKenzie Sept. 20, 1949 2,525,286 Cope .Oct. 10, 1950 2,639,047 Ipsen May 19, 1953 2,915,952 ONeil Dec. 8, 1959 

